The book in an accessible form tells about modern physical ideas regarding the magnetic properties of various substances of the surrounding world. The simplest experiments with permanent magnets and electric currents are considered. Phenomenological description of magnetic phenomena and classification of various types of magnets are given. The question of the connection of the magnetism of atoms with their electronic structure, some questions of the magnetism of elementary particles are described in detail. There are a large number of tasks offered to readers for self-solution.